/***************************************************************************
    copyright            : (C) 2013 by Tsuda Kageyu
    email                : tsuda.kageyu@gmail.com
 ***************************************************************************/

/***************************************************************************
 *   This library is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU Lesser General Public License version   *
 *   2.1 as published by the Free Software Foundation.                     *
 *                                                                         *
 *   This library is distributed in the hope that it will be useful, but   *
 *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
 *   Lesser General Public License for more details.                       *
 *                                                                         *
 *   You should have received a copy of the GNU Lesser General Public      *
 *   License along with this library; if not, write to the Free Software   *
 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA         *
 *   02110-1301  USA                                                       *
 *                                                                         *
 *   Alternatively, this file is available under the Mozilla Public        *
 *   License Version 1.1.  You may obtain a copy of the License at         *
 *   http://www.mozilla.org/MPL/                                           *
 ***************************************************************************/

#include "taglib-config.h"

#include "trefcounter.h"

#if defined(HAVE_STD_ATOMIC)
#  include <atomic>
#  define ATOMIC_INT    std::atomic_int
#  define ATOMIC_INC(x) (++(x))
#  define ATOMIC_DEC(x) (--(x))
#elif defined(HAVE_GCC_ATOMIC)
#  define ATOMIC_INT    int
#  define ATOMIC_INC(x) ::__sync_add_and_fetch(&x, 1)
#  define ATOMIC_DEC(x) ::__sync_sub_and_fetch(&x, 1)
#elif defined(HAVE_WIN_ATOMIC)
#  if !defined(NOMINMAX)
#    define NOMINMAX
#  endif
#  include <windows.h>
#  define ATOMIC_INT    volatile LONG
#  define ATOMIC_INC(x) ::InterlockedIncrement(&x)
#  define ATOMIC_DEC(x) ::InterlockedDecrement(&x)
#elif defined(HAVE_MAC_ATOMIC)
#  include <libkern/OSAtomic.h>
#  define ATOMIC_INT    int32_t
#  define ATOMIC_INC(x) ::OSAtomicIncrement32Barrier(&x)
#  define ATOMIC_DEC(x) ::OSAtomicDecrement32Barrier(&x)
#elif defined(HAVE_IA64_ATOMIC)
#  include <ia64intrin.h>
#  define ATOMIC_INT    int
#  define ATOMIC_INC(x) ::__sync_add_and_fetch(&x, 1)
#  define ATOMIC_DEC(x) ::__sync_sub_and_fetch(&x, 1)
#else
#  define ATOMIC_INT    int
#  define ATOMIC_INC(x) (++(x))
#  define ATOMIC_DEC(x) (--(x))
#endif

namespace Strawberry_TagLib {
namespace TagLib {

class RefCounter::RefCounterPrivate {
 public:
  RefCounterPrivate() : refCount(1) {}

  ATOMIC_INT refCount;
};

RefCounter::RefCounter() : d(new RefCounterPrivate()) {}

RefCounter::~RefCounter() {
  delete d;
}

void RefCounter::ref() {
  ATOMIC_INC(d->refCount);
}

bool RefCounter::deref() {
  return (ATOMIC_DEC(d->refCount) == 0);
}

int RefCounter::count() const {
  return static_cast<int>(d->refCount);
}

bool RefCounter::unique() const {
  return (d->refCount == 1);
}
}  // namespace TagLib
}  // namespace Strawberry_TagLib
